#include <stdio.h>


int factorial(int num)
{
	int i = 0;
	int sum = 1;
	for(i=1;i<=num;++i)
	{
		sum =sum * i;
	}
	printf("n! =  %d\n",sum);
	return 0;
}

int main()
{
	int n;
	scanf("%d",&n);
	factorial(n);

	return 0;
}
